An optical fiber may include a flexible, transparent fiber that is used to transmit light between two ends of the optical fiber. In some cases, optical fibers may be used with components sealed within a hermetic package. For example, one end of the optical fibers may be connected to components within the hermetic package and another end of the optical fibers may be connected to components outside of the hermetic package. An optical fiber feedthrough may be used to permit the optical fibers to pass through a wall of the hermetic package while maintaining the hermetic properties of the hermetic package.